Electric signals may be routed in electronic circuits using various propagation modes or signal types, such as single-ended, differential and common-mode signals. A single-ended signal is typically transported over a single line or terminal, which is referenced to ground. A differential signal is typically transported over a pair of lines or terminals, such that the signal components carried by the two lines are offset by 180°. A common-mode signal is also carried by two lines or terminals, but the signal components in this case are aligned in phase and amplitude. Several types of circuits are known in the art for converting between single-ended signals and differential signals or common-mode signals.